Extreme mass-ratio contact binaries with a high degree of overcontact may be in the late evolutionary stages of the contact phase .
Detailed photometric analyses and orbital period studies of those systems can provide invaluable information for the coalescence scenario of close binary systems , as recently observed in V1309Â Sco .
In this paper the first light curve analysis and period study for the totally eclipsing contact binary AWÂ CrB is presented .
The VR _ { c } I _ { c } CCD photometric light curves are analysed by means of the WD code .
The asymmetry of the light curves is modelled by a cool star spot on the primary component .
It is shown that AW CrB has a high degree of overcontact f  = 75 ~ { } \% and an extreme mass-ratio of q  = 0.10 , placing it among the few contact binaries with the lowest known mass-ratios .
The mean density of the primary component suggest that it has evolved away from the ZAMS . Eighty-four times of minimum light are reported , derived from observations available in public archives , the literature , and the observations presented in this paper .
The orbital period study shows a continuously increasing period , at a rate of { { \mathrm { d } } P / { \mathrm { d } } t } ~ { } = ~ { } 3.58 \times 10 ^ { -7 } ~ { } d~ { } yr ^ { -1 } , suggesting a mass transfer from the secondary component to the primary one , implying a further decreasing mass-ratio .